The present invention relates to apparatus employed to direct forward movement of a rod as it is pushed through a loose medium such as the ground. More particularly, the present invention relates to a directing apparatus having the versatility to direct or not to direct the movement to increase the efficiency of the movement. For convenience, the term "rod" as used herein refers to both a solid shaft or a hollow pipe and is not intended to be limited to any particular type of rod or pipe.
It is well known to push a rod through the ground from one location to another predetermined location beneath the surface of the ground. For example, a rod may be pushed under a road from one side of the road to the other side without creating a trench in the road. As a rod is pushed through a loose medium such as the ground, it encounters variations in density of the medium and may encounter obstacles which cause the rod to deviate from the intended course or path which would result in it arriving at its predetermined destination. It is therefore necessary to correct the forward movement of the rod to bring it back onto the course of movement needed to have the rod arrive at its predetermined destination.
Generally speaking, apparatus for directing forward movement of a rod through a loose medium such as the ground beneath the surface of the ground are known in the art. Typically, these known devices have a directional tip which is fixed in a directing position such that the forward movement of the rod is continuously being directed. In these prior devices, there is no way to disengage or disable the directional feature without removing the entire rod from the ground and removing the directing apparatus from the end of the rod. The removal of a long length of rod from the ground and reinsertion is a time-consuming operation. Therefore, when these prior devices are used, the operator of the pushing apparatus must continuously change direction of the movement of the rod in order to try to effect movement of the rod along a desired path or course. Because the rod is continuously being directed, the continuous changes result in a zig-zag pattern of movement as the rod is pushed through the ground.
As will become apparent from the following disclosure, the apparatus of the present invention includes various features which provide the versatility of either directing the forward movement of the rod or not directing such movement to improve the efficiency of the overall operation of pushing rod through a loose medium such as the ground.
One object of the present invention is to provide an apparatus for directing forward movement of a rod having both the capability of directing the forward movement of the rod or not directing the forward movement of the rod.
Another object of the present invention is to provide an apparatus for directing the forward movement of a rod which permits the rod to be pushed in a straight direction or in a plurality of directions other than the straight direction without withdrawing the rod from the ground and removing the directing apparatus from the end of the rod. Accordingly, the apparatus of the present invention improves the efficiency of movement of the rod along a desired course or path required for the rod to arrive at its predetermined destination.
It is a further object of the present invention to provide a way to direct a fluid such as water or drilling mud into the loose medium in the direction of the forward movement of a rod to condition the loose medium in front of the rod and thereby facilitate the movement of the rod.
According to the present invention, an apparatus for directing the forward movement of a rod as it is moved through a loose medium includes a first member having a proximal end and a distal end, a second member sleeved onto the first member so that the first member is movable relative to the second member, the second member also having a proximal end and a distal end, a directing member provided on either the first member or the second member but in the preferred embodiment, provided on the first member, a connector for coupling the proximal end of the first member to the rod, drive-engaging means on both the first and second members which cooperate to provide driving engagement between the first and second members wherein the directing member is disabled in a first driving position and the directing member is enabled in a second directing position and control means for controlling the disengagement and engagement of the drive-engaging means selectively to permit forward movement of the rod in a desired direction as the rod is being moved through the loose medium.
A further feature of the present invention is that the apparatus for directing forward movement of the rod further includes a first fluid passageway in the first member for transmitting fluid from the proximal end of the first member to the distal end of the first member, a first nozzle means for dispensing the fluid into the loose medium in the direction of the forward movement of the rod when the directing member is disabled, and a second nozzle means for dispensing fluid into the loose medium in the direction of forward movement of the rod when the directing member is enabled. In the preferred embodiment, the first nozzle means includes a first valve means for closing the first nozzle means when the directing member is enabled and for opening the first nozzle means when the directing member is disabled. Further, the second nozzle means includes a second valve means for closing the second nozzle means when the directing member is disenabled and for opening the second nozzle means when the directing member is enabled. The first valve means includes a sealing means and bypass means for bypassing the sealing means when the directing member is disabled.
Other objects, features, and advantages of the present invention will become apparent to those skilled in the art from the following detailed description of preferred embodiments thereof exemplifying the best mode of carrying out the invention as presently perceived.